Diels-Alder reaction with transition metal/zeolites

Transition metal/Y zeolites were prepared by microwave solid state and aqueous solution ion-exchange methods. The activity of these zeolites was investigated in a Diels-Alder reaction of cyclopentadiene and maleic anhydride, anthracene and maleic anhydride. The yield of these reactions increased in order of (NaY<Fe2+Y<Fe3+Y<MnY<CuY approximate to NiY<CoY approximate to CrY<ZnY) for both methods. The aqueous solution ion-exchanged zeolites showed higher activity in comparison to solid state exchange. About 65-70% yield was observed for the Diels-Alder reaction with ZnY Zeolite. Endo-selectivity was observed for these reactions.